Saw this and had to share it - this is the sort of news that makes the internet worthwhile - and it's from New Scientist (so it must be true):

"It will make you go blind. It will make your palms grow hairy. Such myths about masturbation are largely a thing of the past. But the latest research has even better news for young men: frequent self-pleasuring could protect against the most common kind of cancer.

A team in Australia led by Graham Giles of The Cancer Council Victoria in Melbourne asked 1079 men with prostate cancer to fill in a questionnaire detailing their sexual habits, and compared their responses with those of 1259 healthy men of the same age. The team concludes that the more men ejaculate between the ages of 20 and 50, the less likely they are to develop prostate cancer.

The protective effect is greatest while men are in their twenties: those who had ejaculated more than five times per week in their twenties, for instance, were one-third less likely to develop aggressive prostate cancer later in life (BJU International, vol 92, p 211).

The results contradict those of previous studies, which have suggested that having had many sexual partners, or a high frequency of sexual activity, increases the risk of prostate cancer by up to 40 per cent. The key difference is that these earlier studies defined sexual activity as sexual intercourse, whereas the latest study focused on the number of ejaculations, whether or not intercourse was involved.

Saw this and had to share it - this is the sort of news that makes the internet worthwhile - and it's from New Scientist (so it must be true):

"The protective effect is greatest while men are in their twenties: those who had ejaculated more than five times per week in their twenties, for instance, were one-third less likely to develop aggressive prostate cancer later in life "